package com.zifan.sever.controller;

import cn.hutool.core.util.ObjectUtil;
import com.google.code.kaptcha.impl.DefaultKaptcha;
import io.swagger.annotations.ApiOperation;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.IOException;

/**
 * 验证码生成接口
 * @author Zifan
 * @date 2021年04月11日12:15
 */
@RestController
@Slf4j
public class CaptchaController {

    @Autowired
    private DefaultKaptcha defaultKaptcha;

    @ApiOperation(value = "验证码")
    //让swagger中也能看到验证码
    @GetMapping(value = "/captcha",produces = "image/jpeg")
    public void captcha (HttpServletRequest request, HttpServletResponse response){

        //通过响应流直接传一个图片过去，此时需要对响应头做处理。

        // 定义response输出类型为image/jpeg类型
        response.setDateHeader("Expires", 0);
        // Set standard HTTP/1.1 no-cache headers.
        response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
        // Set IE extended HTTP/1.1 no-cache headers (use addHeader).
        response.addHeader("Cache-Control", "post-check=0, pre-check=0");
        // Set standard HTTP/1.0 no-cache header.
        response.setHeader("Pragma", "no-cache");
        // return a jpeg
        response.setContentType("image/jpeg");
        //-------------------生成验证码 begin --------------------------

        //获取验证码文本内容
        String text = defaultKaptcha.createText();
        log.info("验证码内容:{}",text);
        //放入session
        request.getSession().setAttribute("captcha",text);
        //生成的验证码转换为图片
        BufferedImage image = defaultKaptcha.createImage(text);
        ServletOutputStream outputStream = null;
        try {
            outputStream = response.getOutputStream();
            //输出流输出图片，格式为jpg
            ImageIO.write(image,"jpg",outputStream);
            outputStream.flush();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (ObjectUtil.isNotNull(outputStream)){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        //-------------------生成验证码 end --------------------------
    }
}
